Rotationally orientated dual differential hall effect speed and direction gear tooth sensor assembly
a dual-division, gear tooth technology, applied in the field of magneto-magnetic field sensors, to achieve the effect of reducing the spacing between the sensors
Active Publication Date: 2007-07-10
LITTELFUSE INC
View PDF6 Cites 16 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
The invention is a gear tooth sensor assembly that uses two sensor modules with Hall effect sensors to detect the position of gear teeth. The sensor modules are positioned with respect to each other and the gear tooth using selected criteria. The sensor modules are mounted perpendicular to a circuit board, and the leads on the sensor modules are bent at a specific angle to align with the gear tooth. The angle between the sensor modules is determined to create a unique positioning system that allows for the accurate detection of gear tooth position. The technical effects of this invention include improved accuracy and efficiency in the detection of gear tooth position, as well as a more compact and cost-effective design.
Problems solved by technology
If two Hall effect sensors that have been rotated to control the effective spacing between Hall effect sensors on each sensor module are to be used, a problem arises in mounting the two sensor modules in the proper rotation and angular position relative to each other and to the motor gear.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
example
[0038]μ=(Tan-1cos(98.64-90)cos(30)sin(98.64-90)cos(152))-90°=-4.30°
[0039]It should be understood that the spacing of the Hall effect sensors 26, 28 in the circumferential direction and therefore the angle α as well as the angle of rotation β of the individual sensors in the plane of the positioning surface are design variables which may be optimized for a particular gear tooth sensor assembly. Further, it is to be understood that the angles γ to which the leads 52 are bent and the angle μ of the circuit board with respect to a plane tangent to the gear 40 at a point midway between the sensors 26, 28 are derived values selected to achieve the end condition that the leads 52 are perpendicular to the circuit board 24 and thus easily inserted into the circuit board.
[0040]It should be understood that the angle β is selected so that the individual Hall effect sensors 34 are tangent to the gear 40, and the angle α is selected to adjust the effective spacing between the individual ...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
Two sensor modules that each contain two Hall effect sensors are positioned with respect to each other and with respect to a circuit board in a gear tooth sensor assembly. The sensor modules are arranged rotated in the plane of a positioning surface 120° with respect to each other, and tilted toward each other 15°. Sensor leads are bent at an angle of 98.64° such that the leads on both sensors pass perpendicularly through holes in a single circuit board tilted at an angle of 4.30° away from a plane tangent to the gear at a point halfway between the sensors. The sensor package is formed by a plastic mounting bracket arranged to position the sensor modules with respect to each other and the circuit board. The first two angles are selected, and the second two angles are determined so that the sensors are inserted perpendicular to the circuit board.
Description
BACKGROUND OF THE INVENTION[0001]The present invention relates to magnetic field sensors used in sensing gear rotation in general, and to Hall effect sensors mounted to detect ferrous gear teeth in particular.[0002]In order to control a motor using feedback, it is necessary to employ sensors that detect the operation of the motor. If the motor is used to drive a ferrous gear, a simple and reliable sensor that can detect rotation of the ferrous gear can be constructed based on a Hall effect sensor. Sophisticated sensor modules that incorporate a magnet and a ferrous pole piece and one or two Hall effect sensors are available from a number of manufacturers. When the sensor module is placed so that the Hall effect sensors are within about zero to 2.5 mm from the peripheral edge of a ferrous gear, passage of the gear tooth past the Hall effect sensors creates an increase in magnetic field strength which is detected by the Hall effect sensors. By using a sensor module that incorporates t...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & AuthorityPatents(United States)
IPC IPC(8): G01B7/30
CPCG01P1/026G01P3/487G01D5/2451G01P3/488G01D5/145G01D5/00G01D5/12
InventorO'CONNOR, KEVIN P.
OwnerLITTELFUSE INC